Endoscopic surgery is a minimally invasive surgical procedure that is performed through small incisions or natural body openings. An endoscopic procedure typically involves use of specialized devices and remote-control manipulation of instruments with indirect observation of the surgical field through an endoscope or similar device. Comparing to open surgery, endoscopic surgery may result in shorter hospital stays, or allow outpatient treatment.
Trigger finger is characterized by catching, snapping or locking of the involved finger flexor tendon, associated with dysfunction and pain. Localized inflammation or nodular swelling of said flexor tendon causes a disparity in size between the flexor tendon and the surrounding retinacular pulley system, most commonly at the level of the first annular (A1) pulley. When the subject extends the involved finger, the tendon will “catch” on the pulley, followed by an abrupt popping of the tendon through the pulley. This results in a difficulty flexing or extending the finger and the “triggering” phenomenon. Typically, a first course of treatment for trigger finger is corticosteroid injections into the tendon sheath to reduce inflammation. When corticosteroid injection is not or no longer effective, surgical division of the A1 pulley is indicated.
Carpal tunnel syndrome is an entrapment median neuropathy resulting from compression of the median nerve at the wrist in the carpal tunnel. Symptoms of carpal tunnel syndrome include tingling, numbness, weakness, or pain felt in the fingers supplied by the median nerve or in the palm. Repetitive tasks, force, posture, and vibration have been cited as causative or contributing factors to carpal tunnel syndrome. Palliative treatments for carpal tunnel syndrome include direct corticosteroid injections, splinting, oral corticosteroids and/or behavior modification. Failure of these methods within a reasonable period of time, and/or the presence of other contributing factors, indicates a need for surgical division of the carpal tunnel.
Other conditions involving the compression of a nerve by a ligament pulley or tunnel include Guyon's canal (or canal) syndrome, which is a compression of the ulnar nerve as it passes through Guyon's canal at the wrist; cubital tunnel syndrome, which is a compression of the ulnar nerve as it passes through the cubital tunnel at the elbow; radial tunnel syndrome, which is a compression of the radial nerve as it travels from the brachial plexus to the wrist and hand; and pronater teres syndrome, which is a compression neuropathy of the median nerve in the region of the elbow.
Conventional surgical techniques and equipment for pulley or tunnel release require a fairly large incision over the pulley or tunnel and spreading of the incision to allow viewing and instrument access. These techniques can require a longer period of recovery than endoscopic methods and have greater levels of post-operative pain due to the incision size and level of manipulation during the procedure.
Typically, endoscopic surgery has involved a number of steps and separate devices for performing pulley or tunnel division. After making an incision and opening a path to the pulley or tunnel using a blunt instrument, a cannula is inserted into the path. Briefly, in order to smoothly insert the cannula, the central lumen of the cannula must be filled with a device, such as an obturator. The obturator is then removed and an endoscope, or arthroscope, is inserted into the cannula to view the pulley or tunnel. The endoscope is then withdrawn from the cannula, a knife is either advanced into the cannula for division or a specialized knife assembly is affixed to the endoscope and the knife/endoscope assembly is advanced into the cannula for division. The present application fulfills a need in the art for a compact device for uniportal endoscopic pulley or tunnel release surgery that eliminates the need for a separate device, such as an obturator, for filling the cannula during insertion and eliminates the need to remove the endoscope in order to insert a blade or blade assembly.